The present invention relates to an electrical machine and to a drive device.
Drive devices, preferably hybrid drive devices, in particular comprising an internal combustion engine and an electrical machine, are used, for example, in order to drive motor vehicles. The electrical machine in the motor vehicle, which electrical machine operates as a motor and a generator, has an axle or shaft on which the stator or rotor is arranged.
Waste heat is produced in the electrical machine, in particular in the stator and/or rotor, and therefore it is necessary to cool the electrical machine. The stator and rotor are arranged within a housing of the electrical machine. A spiral or helical channel for conducting a cooling fluid for cooling the electrical machine is incorporated in the housing. The axle around which the spiral cooling channel is wound corresponds to the axis of the shaft of the electrical machine in this case. After the cooling fluid is introduced into the channel, the cooling fluid absorbs heat and thus is at a higher temperature. This leads to non-uniform temperature distribution over the axial length of the electrical machine. Therefore, the absorption of heat by the cooling fluid is disadvantageously reduced.
DE 199 28 247 B4 describes a motor having a motor housing, a stator of cylindrical shape which is mounted on the motor housing, an internal rotor which is arranged in a rotatable manner within the stator, an external rotor which is arranged in a rotatable manner about the stator, with the internal rotor, the stator and the external rotor being arranged in a concentric manner and having a plurality of pins for mounting the stator on the motor housing, with a cooling system being provided which has a plurality of pairs of cooling channels which are formed in the stator, a coolant inlet opening for introducing coolant into the cooling channels, a coolant outlet opening for diverting coolant from the cooling channels, with the coolant inlet opening and the coolant outlet opening being provided at an axial end of the internal rotor and being connected to the cooling channels, a coolant return section for connecting each pair of cooling channels, with the coolant return section being provided at another axial end of the internal rotor, and with the cooling channels being formed from the stator and the plurality of pins.